Abstract
A change of deformation modes in lattice instable Ti-14 mass%Mo alloy single crystals upon aging treatments at 623 K was investigated in the tensile test up to rupture. The tensile direction of these specimens was [116]B. The main deformation modes of as-quenched specimen (AQ) were {332} 〈113〉 and {112} 〈111〉 mechanical twins. Their Schmid factors (SF) were 0.321 and 0.156 in {332} 〈113〉 twins and 0.447 in {112} 〈111〉 twins. A specimen aged for a short time of nearly 250 s (AG (S)) showed a kind of transitional state of deformation mode which involved {332} 〈113〉 twins, {112} 〈111〉 twins and {112} 〈111〉 slips. In this state AG(S) had been already poor in ductility. A specimen long aged for 1 × 105 s (AG(L)) showed a remarkable brittle fracture caused by the aged ω phase, but it was not the {001} cleavage fracture. The fracture surface had a chevron pattern induced by the operation of some {112} slip systems in the initial stage. Large grown aged ω variants caused the B matrix to remarkably increase the stress level for deformation and induced locally an Ω→B inverse transformation. Local softening which occurred with the inverse transformation led to an extreme stress concentration and then to crack. In this way AG(L) apparently showed notable embrittlement.
| Original language | English |
|---|---|
| Pages (from-to) | 1004-1012 |
| Number of pages | 9 |
| Journal | Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals |
| Volume | 53 |
| Issue number | 10 |
| Publication status | Published - Oct 1989 |
Fingerprint
ASJC Scopus subject areas
- Metals and Alloys
Cite this
Change of deformation mode caused by aging of Ti-14 mass%Mo alloy single crystals and embrittlement mechanism due to the ω-phase. / Takemoto, Yoshito; Hida, Moritaka; Sukedai, Eiiti; Sakakibara, Akira.
In: Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals, Vol. 53, No. 10, 10.1989, p. 1004-1012.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Change of deformation mode caused by aging of Ti-14 mass%Mo alloy single crystals and embrittlement mechanism due to the ω-phase
AU - Takemoto, Yoshito
AU - Hida, Moritaka
AU - Sukedai, Eiiti
AU - Sakakibara, Akira
PY - 1989/10
Y1 - 1989/10
N2 - A change of deformation modes in lattice instable Ti-14 mass%Mo alloy single crystals upon aging treatments at 623 K was investigated in the tensile test up to rupture. The tensile direction of these specimens was [116]B. The main deformation modes of as-quenched specimen (AQ) were {332} 〈113〉 and {112} 〈111〉 mechanical twins. Their Schmid factors (SF) were 0.321 and 0.156 in {332} 〈113〉 twins and 0.447 in {112} 〈111〉 twins. A specimen aged for a short time of nearly 250 s (AG (S)) showed a kind of transitional state of deformation mode which involved {332} 〈113〉 twins, {112} 〈111〉 twins and {112} 〈111〉 slips. In this state AG(S) had been already poor in ductility. A specimen long aged for 1 × 105 s (AG(L)) showed a remarkable brittle fracture caused by the aged ω phase, but it was not the {001} cleavage fracture. The fracture surface had a chevron pattern induced by the operation of some {112} slip systems in the initial stage. Large grown aged ω variants caused the B matrix to remarkably increase the stress level for deformation and induced locally an Ω→B inverse transformation. Local softening which occurred with the inverse transformation led to an extreme stress concentration and then to crack. In this way AG(L) apparently showed notable embrittlement.
AB - A change of deformation modes in lattice instable Ti-14 mass%Mo alloy single crystals upon aging treatments at 623 K was investigated in the tensile test up to rupture. The tensile direction of these specimens was [116]B. The main deformation modes of as-quenched specimen (AQ) were {332} 〈113〉 and {112} 〈111〉 mechanical twins. Their Schmid factors (SF) were 0.321 and 0.156 in {332} 〈113〉 twins and 0.447 in {112} 〈111〉 twins. A specimen aged for a short time of nearly 250 s (AG (S)) showed a kind of transitional state of deformation mode which involved {332} 〈113〉 twins, {112} 〈111〉 twins and {112} 〈111〉 slips. In this state AG(S) had been already poor in ductility. A specimen long aged for 1 × 105 s (AG(L)) showed a remarkable brittle fracture caused by the aged ω phase, but it was not the {001} cleavage fracture. The fracture surface had a chevron pattern induced by the operation of some {112} slip systems in the initial stage. Large grown aged ω variants caused the B matrix to remarkably increase the stress level for deformation and induced locally an Ω→B inverse transformation. Local softening which occurred with the inverse transformation led to an extreme stress concentration and then to crack. In this way AG(L) apparently showed notable embrittlement.
UR - http://www.scopus.com/inward/record.url?scp=0024752860&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024752860&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0024752860
VL - 53
SP - 1004
EP - 1012
JO - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
JF - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
SN - 0021-4876
IS - 10
ER -